1. Field of the Invention
This invention relates to a printing plate mounting apparatus for mounting printing plates peripherally of a plate cylinder.
2. Description of the Related Art
Such a printing plate mounting apparatus includes a forward-end clamping jaw disposed peripherally of a plate cylinder for pinching the forward end of a printing plate with a clamping base, and a rear-end clamping jaw disposed peripherally of the plate cylinder for pinching the rear end of the printing plate with a clamping base. In the conventional printing plate mounting apparatus, the forward-end clamping jaw and rear-end clamping jaw are opened and closed manually. In order to open and close the clamps automatically, clamp switching devices are arranged outwardly of the plate cylinder.
That is, in the conventional printing plate mounting apparatus, the forward-end clamping jaw and rear-end clamping jaw are biased by springs or the like in directions for contacting the clamping bases, respectively. When opening the forward-end clamping jaw and rear-end clamping jaw, air cylinders or the like arranged peripherally of the plate cylinder are used to move the forward-end clamping jaw and rear-end clamping jaw away from the respective clamping bases. Such a printing plate mounting apparatus is disclosed in Japanese Examinated Utility Model Publication 1992-6915, for example.
With the construction noted above for moving the forward-end clamping jaw and rear-end clamping jaw away from the clamping bases by using air cylinders or the like arranged peripherally of the plate cylinder, the plate cylinder must be set to a predetermined angular position and fixed firmly thereto against rotation by the pressing forces of the air cylinders. Thus, not only are plate feeding and removing operations time-consuming, but the apparatus is complicated in construction.